The present invention is related to the field of data processing, in particular to storage-related operation of data processing systems.
In data processing systems, it is known to utilize a stack of input/output (I/O) functional components or drivers in a host computer to realize an interface to an external data storage system. The functional components of an I/O interface stack generally perform different types of functions at different logical layers in a coordinated fashion in order to obtain all the desired functionality of the interface. As an example, a high-level I/O driver may interact with a so-called “multipathing” driver that has knowledge of multiple distinct paths to storage devices and that uses the knowledge to distribute storage I/O commands among the different paths in a way that improves performance or achieves other system goals (such as enhanced availability). The multipathing driver in turn relies one or more lower-level drivers that control the operation of a host bus adapter providing a hardware-level interface to a storage-oriented interconnect bus that connects the host computer to the storage system.